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• Custom metrics can affect the performance.
• We do not provide varuous useful metric implementatons.
• Custom metrics aren't stored and require re-registration after node restart. At least at the first phase.

Phases

In future, we could expose The custom metric API might be also enriched with more complex metrics like historgams. We could also store custom metrics and their configurations. Thus, the development steps might be:

1. Implementation of the described API.
2. Extending the API with metrics like Histogram, HitRate. Allowing to configure metrics.
3. Storing registered custom metrics with their configurations.

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